The goal of the Physiological and Behavioral Outcomes and Analyses Core is to increase the use of minimally invasive physiological and behavioral measures that signal change in the severity of chronic illness or risk for chronic illness, and to provide consultation on design and analytical techniques, emphasizing recent advances in longitudinal analysis. The Core will use five strategies to increase of the use of physiological and behavioral measures and automated data acquisition devices: I) methodological consultation on the selection and use of physiological and behavioral variables and assessment of the reliability and validity of these measures, 2) assistance in the development of minimally invasive physiological and automated data collection procedures, 3) provision of shared equipment and facilities for non-invasive testing, 4) assistance in training research staff on physiological and behavioral measures and automated data acquisition devices and 5) provision of engineering support for the development of automated data collection techniques and maintenance and quality control of this equipment. The Core will also provide forums for Center investigators to discuss measurement issues that arise during the course of their studies, develop strategies for integrating physiological and behavioral measures within the same study, and compare the strengths and limitations of physiological and behavioral variables measuring similar constructs. The Core will also provide statistical consultation for newer statistical techniques that are particularly germane to studying the trajectory of chronic illness and the impact of interventions over time. Thus, the Core will emphasize expanding the use of longitudinal techniques (general mixed linear models, structural equation modeling, event history analysis, longitudinal pattern analysis, time series analyses) uniquely suited to the analysis of physiological and behavioral data. In- depth seminars will be offered in these statistical techniques. Consultation will also be available on data management of complex data sets. ***********************************************************